A top European human rights official has criticised Greece following a deadly boat accident.

A fishing boat crammed with migrants capsized near Farmakonisi, a tiny Greek island in the Aegean Sea near Turkey.

The boat was being towed by a coast guard vessel. The bodies of a woman and an 11-year-old boy were found. A further 10 people were missing, among them infants and children.

The UN Refugee Agency (UNHCR) issued a statement saying it is “dismayed” to have learned of the tragedy.

The survivors, now on the island of Leros, told UNHCR they were being towed in the direction of Turkey at the time of the accident.

The European Council on Refugees and Exiles (ECRE) has reported that refugees attempting to cross the EU’s external borders with Turkey are systematically pushed back from Greek territorial waters, the Greek islands and from the land border.

Another NGO, Pro Asyl, issued a report last November specifically outlining violations that had occurred in the proximity of Farmakonisi.

“It is highly likely that this action by the Greek coast guard was an illegal push-back operation rather than a rescue at sea,” said Karl Kopp, Director of European Affairs with Pro Asyl.

The UN has called for an inquiry. “UNHCR is urging the authorities to investigate this incident and how lives were lost on a boat that was under tow,” said Laurens Jolles, UNHCR’s Southern Europe Regional Representative.

“In addition survivors need to be quickly moved to the mainland so that their needs can be better looked after,” Jolles added.

The incident is the first of its kind in 2014, and the latest in a string of recent boat disasters in the Mediterranean involving people fleeing by sea towards Europe.

More than 360 people died on October 3, 2013 in a capsizing off of Italy’s Lampedusa. Several other deadly incidents were reported over the following weeks.

Greece has become a main point of entry for unauthorised migrants heading toward Europe.